# What Would Happen If I Used Coffee (Instead of Water) to Make Coffee? **URL:** \ **Category:** Factual Questions\ **Created:** [November 17, 2012, 4:17pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317 "2012-11-17T16:17:56Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [November 18, 2012, 1:59am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/21 "2012-11-18T01:59:03Z")
> [@Leo\_Bloom](#): > > So why is espresso so strong, oz. to oz.? Because you use as much ground coffee to make a shot of espresso as you would to make a half a pot of coffee. ---
**Author:** ![Darryl\_Lict](https://avatars.discourse-cdn.com/v4/letter/d/7cd45c/32.png) [@Darryl\_Lict](https://boards.straightdope.com/u/Darryl_Lict)\ **Post date:** [November 18, 2012, 2:00am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/22 "2012-11-18T02:00:54Z")
I happen to be drinking a cup of drip coffee so in the interest of science, I ran the pot through another batch of grounds. Well, the result is unsurprisingly, strong black coffee, not unlike you would get if you used twice as much ground coffee. I poured the one time coffee and the two time coffee into martini glasses and observed the color variation. The twice brewed coffee is super dark and even at the apex of the cone, it’s still pretty damn dark. Actually, a martini glass is a really great tool for observing subjective differences in optical density of a fluid. ---
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [November 18, 2012, 2:25am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/23 "2012-11-18T02:25:32Z")
If you’re looking for the big caffeine kick, just use caffeinated water. Again, you’ll need to clean your coffee maker more often, but hey. Caffeine. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [November 18, 2012, 2:28am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/24 "2012-11-18T02:28:55Z")
> [@Francis\_Vaughan](#): > > Using coffee instead of water will leave a residue of coffee in the chamber which will burn and stick, and eventually kill your machine. Correct - for values of “eventually” that include “promptly”. I once worked in an office whose staff included a woman who could not grasp the finer points of “Pour in water only.” She killed 3 machines before being banned from the break room. ---
**Author:** ![Johnny\_Angel](https://avatars.discourse-cdn.com/v4/letter/j/d26b3c/32.png) [@Johnny\_Angel](https://boards.straightdope.com/u/Johnny_Angel)\ **Post date:** [November 18, 2012, 5:16am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/25 "2012-11-18T05:16:15Z")
My electronics instructor in high school used to pour his cold coffee back into the coffee maker and brew it again. It looked… viscous. But I never tried tasting it. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [November 18, 2012, 2:35pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/26 "2012-11-18T14:35:22Z")
> [@Michael63129](#): > > What actually happens is that volatile chemicals evaporate, which is why old coffee loses its flavor (saying this because apparently there is a [myth](http://www.gourmetcoffeeshop.net/reheated-coffee-and-health.htm) that doing so makes it toxic, which is certainly believable if you have tasted it, and why wouldn’t the same toxic substances form when coffee is brewed?). Certainly the volatiles evaporate and flavor deteriorates over time. I’m a rabid home espresso brewer who consumes at least 2 shots of espresso a day, and am well-versed in the proper process and importance of those wonderful, wonderful volatiles. But the volatiles are a small percentage of molecular compounds in coffee. Otherwise evaporation of coffee would leave water! It’s the remaining molecular compounds which, upon re-heating undergo further molecular changes that even further degrade the flavor of what remains. And gum up the coffee maker ---
**Author:** ![cwthree](https://avatars.discourse-cdn.com/v4/letter/c/9de0a6/32.png) [@cwthree](https://boards.straightdope.com/u/cwthree)\ **Post date:** [November 18, 2012, 2:52pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/27 "2012-11-18T14:52:33Z")
> [@TriPolar](#): > > I know someone who made coffee that way in an office coffee pot. He just stuffed two of those filter donuts into the coffee machine. Everyone loved it (except me, I won’t go near the stuff). Since it was my office and I was paying for the coffee I made them start contributing to the cost if they were going to do that. Did you work with me? My coworker like to use two coffee packets and/or two filters (to slow down the flow of water through the coffee). This produced a brew of such toxic intensity that the office manager gave him his own labelled coffee pot. For his going-away party, we had it mounted on a trophy base with a biohazard symbol on it and gave it to him to take with. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 18, 2012, 5:43pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/28 "2012-11-18T17:43:46Z")
if a spoon won’t stand up on its own then it’s not strong enough. ---
**Author:** ![Agent\_Foxtrot](https://avatars.discourse-cdn.com/v4/letter/a/9fc29f/32.png) [@Agent\_Foxtrot](https://boards.straightdope.com/u/Agent_Foxtrot)\ **Post date:** [November 20, 2012, 9:00pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/29 "2012-11-20T21:00:39Z")
Is anyone currently staying in a hotel room? Try it with the room coffee maker. ---
**Author:** ![tanstaafl](https://avatars.discourse-cdn.com/v4/letter/t/ba8739/32.png) [@tanstaafl](https://boards.straightdope.com/u/tanstaafl)\ **Post date:** [November 20, 2012, 9:07pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/30 "2012-11-20T21:07:21Z")
> [@cwthree](#): > > Did you work with me? My coworker like to use two coffee packets and/or two filters (to slow down the flow of water through the coffee). This produced a brew of such toxic intensity that the office manager gave him his own labelled coffee pot. For his going-away party, we had it mounted on a trophy base with a biohazard symbol on it and gave it to him to take with. That’s the _standard_ at my office. Shortly after starting here I made a pot with a single filter pack. Someone got a cup, took a drink then dumped the whole pot out and made a new one, after which I was told to _never_ make a pot with just one filter pack again. Two is standard. Three happens often on Monday mornings. I’ve see people using 4. I’ve taken to just getting a half cup and filling it up the rest of the way with hot water. ---
**Author:** ![Jimbob48](https://avatars.discourse-cdn.com/v4/letter/j/edb3f5/32.png) [@Jimbob48](https://boards.straightdope.com/u/Jimbob48)\ **Post date:** [March 8, 2017, 11:10am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/31 "2017-03-08T11:10:59Z")
> [@HeyHomie](#): > > Let’s say I poured my existing pot of coffee into the reservoir in my coffee maker where I’d ordinarily pour water. Would the resulting pot of coffee > > [ul] > [li]Be undrinkable[/li][li]Be indistinguishable from coffee made with water[/li][li]Be awesome (if one likes strong coffee, that is)[/li][li]Blow up my coffee maker[/li][/ul] > > ? > > Thanks! It will clog the reservoir “Homie” lol! ---
**Author:** ![Count\_Blucher](https://avatars.discourse-cdn.com/v4/letter/c/c5a1d2/32.png) [@Count\_Blucher](https://boards.straightdope.com/u/Count_Blucher)\ **Post date:** [March 8, 2017, 11:29am UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/32 "2017-03-08T11:29:28Z")
> [@Jimbob48](#): > > It will clog the reservoir “Homie” lol! Well, sure! You do that for FIVE STRAIGHT YEARS, the internal piping will probably be solid all the way through. I’m not even sure How you’d clean that mess. Brew a reservoir of white vinegar 50 times a day for a month? **[SIZE=“1”]“_Grains…! Grains…!_” - Zombie Alexa Hente**[/SIZE] ---
**Author:** ![Monty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/monty/32/47_2.png) [@Monty](https://boards.straightdope.com/u/Monty)\ **Post date:** [March 8, 2017, 2:37pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/33 "2017-03-08T14:37:53Z")
What about [vacuum coffee makers](https://en.m.wikipedia.org/wiki/Vacuum_coffee_maker)? How is the coffee made using those? ---
**Author:** ![Evan\_Drake](https://avatars.discourse-cdn.com/v4/letter/e/b487fb/32.png) [@Evan\_Drake](https://boards.straightdope.com/u/Evan_Drake)\ **Post date:** [March 8, 2017, 2:53pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/34 "2017-03-08T14:53:42Z")
Try pouring whisky neat into the reservoir. ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [March 8, 2017, 4:39pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/35 "2017-03-08T16:39:32Z")
I can tell you from experience that coffee made from Sprite is _not good_. Just to remove that 0.001% of doubt that might have been in your mind. ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [March 8, 2017, 5:39pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/36 "2017-03-08T17:39:51Z")
> [@Darryl\_Lict](#): > > Actually, a martini glass is a really great tool for observing subjective differences in optical density of a fluid. Thank you for this sentence. I know it’s years later and all, but still. ---
**Author:** ![Daylate](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Daylate](https://boards.straightdope.com/u/Daylate)\ **Post date:** [March 8, 2017, 6:03pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/37 "2017-03-08T18:03:52Z")
Regarding vacuum pot coffee, I’d like to warn Dopers about something NOT to do. Back in the days that I used a vacuum pot (you know, the type that uses two glass containers, one on the bottom that holds the water, and one on top that that holds the coffee grounds, with a filter between them to keep the grounds out of the finished coffee). I had only about half the amount of fresh ground coffee needed, so I just made up the shortfall from my wife’s jar of instant coffee, and put that in the upper pot along with the regular grounds. Then I lit the fire under the bottom pot. Everything proceeded normally until the upper pot was full of hot water, and the coffee began being pulled back down into the lower part. Almost immediately there was a BIG explosion (it was actually an implosion) and broken glass and hot coffee flew all over the kitchen. Scared the heck out of me. Turns out that the instant coffee I put in there immediately clogged up the filter. Then, as the system cooled off, the vacuum in the lower pot increased until the glass could no longer resist the outside pressure, and let go. Quite a mess to clean up. Last time I tried that trick. Nowadays I make all my coffee courtesy of a nice easy Kurig coffee-maker, and never have any trouble. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [March 8, 2017, 6:23pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/38 "2017-03-08T18:23:27Z")
Basically, a coffee maker heats water to near boiling, then runs it through the rounds one way or another. Substitute anything that includes organic compounds for “water” and you are basically heating those organic compounds. Heat tends to break down a lot of organic compounds - they break down, they oxidize, they combine. Ever tasted a coffee from a pot that’s been on the burned too long? Heat milk or anything with sugar, it caramelizes. I suspect the flavorful molecules in coffee are complex enough that they could break down if subject to higher heat for too long, and a heating element for boiling water tends to get much hotter than the temperature of the water that finally reaches a coffee grounds and filter. Of course, as the stuff burns, it may also have a tendency to stick to things - creating a mess, slowing liquid flows, and making the heating element or the parts nearest it less efficient. ---
**Author:** ![nightshadea](https://avatars.discourse-cdn.com/v4/letter/n/7ba0ec/32.png) [@nightshadea](https://boards.straightdope.com/u/nightshadea)\ **Post date:** [March 8, 2017, 7:26pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/39 "2017-03-08T19:26:46Z")
shouldn’t this get moved to café? you just get stronger coffee…my house uses a 40 cup office pot and sometimes they just fill up whats left with water and put new in … ---
**Author:** ![nightshadea](https://avatars.discourse-cdn.com/v4/letter/n/7ba0ec/32.png) [@nightshadea](https://boards.straightdope.com/u/nightshadea)\ **Post date:** [March 8, 2017, 7:58pm UTC](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317/40 "2017-03-08T19:58:51Z")
actually form experience using non water substances clog up the machiene …see my cousin uses grove square French vanilla cappuccino cups and its just instant coffee and flavored non dairy creamer but I have to rinse everything out because it leaves a type of sticky pudding film substance that is very proficient at growing mold … I wiuld think the same happens in a normal coffee pot also [Previous page](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317.md?page=1) [Next page](https://boards.straightdope.com/t/what-would-happen-if-i-used-coffee-instead-of-water-to-make-coffee/641317.md?page=3)